EIBOS Tetras Review: Four Independent Drying Chambers for Bambu Lab AMS

Four chambers, one AMS

The EIBOS Series X Tetras is an upgrade module designed specifically for Bambu Lab AMS users. Instead of adding a separate filament dryer to your desk, the Tetras mounts directly to the AMS frame and splits it into four independently controlled drying chambers.

Each chamber runs its own heating unit and control panel. You can set different temperatures and drying times for each spool. That matters when you are switching between PLA, PETG, ABS, and TPU in a single print job. A review from 3DWithUs highlighted the ability to run four different materials at once without compromise.

Print while you dry

The Tetras is built for continuous use. Active air circulation forces dry air into each sealed chamber and removes moisture. The system does not need to pause when the printer starts. Filament feeds directly from the dryer into the AMS and then to the toolhead without any manual transfer.

EIBOS also includes a second-stage drying step that holds filament at a stable humidity level between uses. The company says this reduces stringing, warping, and under-extrusion caused by damp spool. For anyone who has abandoned a multicolor print halfway through because one filament absorbed moisture, the Tetras offers a practical workaround.

Installation and compatibility

The Tetras works with the Bambu Lab AMS and AMS2 Pro. Owners of the AMS2 Pro need a self-printed adapter available on MakerWorld. Setup is straightforward: the kit includes all modules, cables, and fasteners. No printer firmware changes are required, and the dryer runs on its own power supply separate from the printer.

The full Tetras unit draws 240W across four chambers. The smaller Dyas model with two chambers draws 120W. Both versions sit neatly on top of the AMS unit and add minimal footprint to the printer. Each bay is isolated with feed baffles and acrylic dividers, so airflow stays contained and cross-contamination between chambers is unlikely.

Real-world testing

In a recent video from EDGE OF 3D, the presenter tested the Tetras alongside the Bambu Lab X1C. The setup process took under an hour, and each chamber reached operating temperature within about 15 minutes. Once running, the system maintained consistent humidity levels across all four bays while a multicolor print was underway.

The video noted that the independent control panels are functional but basic. Each chamber has its own small screen for setting temperature and timer, which works well for quick adjustments. However, users accustomed to unified touchscreen interfaces may find the four separate displays a bit cluttered at first.

Print quality tests showed noticeable improvement in layer adhesion and surface finish when switching from damp storage to freshly dried filament. Stringing dropped on PETG and ABS tests, and overhang performance improved because the extruder was feeding material at a consistent moisture level.

Who should buy it

The Tetras makes most sense for users who already own a Bambu Lab AMS and run multicolor prints regularly. If you only use one or two filaments and dry them between jobs, a standalone dryer may still be cheaper. But if you keep four spools loaded and switch materials often, the Tetras removes a repetitive unload-reload cycle.

The system is not cheap, and the AMS2 Pro adapter requires a 3D printed part. But the modular design means you can add chambers as your material library grows. For users frustrated by filament moisture ruining surface finish, the Tetras is a targeted fix that keeps your workflow inside one ecosystem.